1 files changed, 97 insertions, 0 deletions
diff --git a/js/src/vm/DateObject.h b/js/src/vm/DateObject.h
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+++ b/js/src/vm/DateObject.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef vm_DateObject_h_
+#define vm_DateObject_h_
+
+#include "js/Date.h"
+#include "js/Value.h"
+#include "vm/NativeObject.h"
+
+namespace js {
+
+class DateObject : public NativeObject {
+  // Time in milliseconds since the (Unix) epoch.
+  static const uint32_t UTC_TIME_SLOT = 0;
+
+  // Raw time zone offset in seconds, i.e. without daylight saving adjustment,
+  // of the current system zone.
+  //
+  // This value is exclusively used to verify the cached slots are still valid.
+  //
+  // It is NOT the return value of Date.prototype.getTimezoneOffset()!
+  static const uint32_t UTC_TIME_ZONE_OFFSET_SLOT = 1;
+
+  /*
+   * Cached slots holding local properties of the date.
+   * These are undefined until the first actual lookup occurs
+   * and are reset to undefined whenever the date's time is modified.
+   */
+  static const uint32_t COMPONENTS_START_SLOT = 2;
+
+  static const uint32_t LOCAL_TIME_SLOT = COMPONENTS_START_SLOT + 0;
+  static const uint32_t LOCAL_YEAR_SLOT = COMPONENTS_START_SLOT + 1;
+  static const uint32_t LOCAL_MONTH_SLOT = COMPONENTS_START_SLOT + 2;
+  static const uint32_t LOCAL_DATE_SLOT = COMPONENTS_START_SLOT + 3;
+  static const uint32_t LOCAL_DAY_SLOT = COMPONENTS_START_SLOT + 4;
+
+  /*
+   * Unlike the above slots that hold LocalTZA-adjusted component values,
+   * LOCAL_SECONDS_INTO_YEAR_SLOT holds a composite value that can be used
+   * to compute LocalTZA-adjusted hours, minutes, and seconds values.
+   * Specifically, LOCAL_SECONDS_INTO_YEAR_SLOT holds the number of
+   * LocalTZA-adjusted seconds into the year. Unix timestamps ignore leap
+   * seconds, so recovering hours/minutes/seconds requires only trivial
+   * division/modulus operations.
+   */
+  static const uint32_t LOCAL_SECONDS_INTO_YEAR_SLOT =
+      COMPONENTS_START_SLOT + 5;
+
+  static const uint32_t RESERVED_SLOTS = LOCAL_SECONDS_INTO_YEAR_SLOT + 1;
+
+ public:
+  static const JSClass class_;
+  static const JSClass protoClass_;
+
+  JS::ClippedTime clippedTime() const {
+    double t = getFixedSlot(UTC_TIME_SLOT).toDouble();
+    JS::ClippedTime clipped = JS::TimeClip(t);
+    MOZ_ASSERT(mozilla::NumbersAreIdentical(clipped.toDouble(), t));
+    return clipped;
+  }
+
+  const js::Value& UTCTime() const { return getFixedSlot(UTC_TIME_SLOT); }
+
+  // Set UTC time to a given time and invalidate cached local time.
+  void setUTCTime(JS::ClippedTime t);
+  void setUTCTime(JS::ClippedTime t, MutableHandleValue vp);
+
+  inline double cachedLocalTime();
+
+  // Cache the local time, year, month, and so forth of the object.
+  // If UTC time is not finite (e.g., NaN), the local time
+  // slots will be set to the UTC time without conversion.
+  void fillLocalTimeSlots();
+
+  const js::Value& localYear() const {
+    return getReservedSlot(LOCAL_YEAR_SLOT);
+  }
+  const js::Value& localMonth() const {
+    return getReservedSlot(LOCAL_MONTH_SLOT);
+  }
+  const js::Value& localDate() const {
+    return getReservedSlot(LOCAL_DATE_SLOT);
+  }
+  const js::Value& localDay() const { return getReservedSlot(LOCAL_DAY_SLOT); }
+
+  const js::Value& localSecondsIntoYear() const {
+    return getReservedSlot(LOCAL_SECONDS_INTO_YEAR_SLOT);
+  }
+};
+
+}  // namespace js
+
+#endif  // vm_DateObject_h_